How to show vertices on a cube when selected?

I’m trying to write a script that makes a cube turn blue and display the vertices of the cube on it when selected. So basically on click it will show all the vertices and then allow a user to select different vertices of the cube. This is what i have so far… essentially only turning the cube blue. How can I display vertices of the cube as spheres that can be selected?

    using UnityEngine;
    using System.Collections;

    public class Cube : MonoBehaviour {

        // Use this for initialization
        void Start() {

        }

        // Update is called once per frame
        void Update() {

        }

        void OnMouseDown() {
            Renderer rend = GetComponent<Renderer>();
            rend.material.color = Color.blue;
            //insert method to display vertices
        }
    }

Answer on c# - How to show vertices on a cube when selected in Unity (during runtime)? - Stack Overflow